南京大学学报（自然科学版）2025，Vol.61Issue(3)：425-440,16.DOI:10.13232/j.cnki.jnju.2025.03.007
次网格地形重力波拖曳对四川东部一次强降水的影响和机理
Impact of subgrid orographic gravity wave drag on a heavy rainfall event in eastern Sichuan Province
摘要
Abstract
This study analyzed the precipitation characteristics and circulation background of the heavy rainfall event in eastern Sichuan on July 26,2023,using China Meteorological Administration Multi-source Merged Precipitation Analysis System(CMPAS)and ERA5 reanalysis data from the European Centre for Medium-Range Weather Forecasts.Sensitivity experiments were conducted using the WRF V4.2.2 mesoscale numerical model.The model performance was quantitatively assessed using correlation coefficients(CC),root mean square error(RMSE),and threat score(TS).The study explored the impact and mechanisms of subgrid orographic gravity wave drag(OGWD)on the heavy rainfall event.Additionally,the Barnes filter was applied to perform scale separation of the circulation fields,enabling a detailed analysis of the influence of circulation at different scales on the precipitation process.The results indicate that the WRF model simulates the precipitation area too far eastward,but the inclusion of OGWD significantly improves the precipitation location bias.Orographic gravity wave drag primarily affects the wind field:at mid-to-upper levels of the troposphere,it weakens the northwesterly winds behind the plateau vortex,at lower levels of the troposphere,it weakens the southeasterly winds transporting moisture into the Sichuan Basin,resulting in a reduction of the northerly winds along the northern and western edges of the basin.This change alters the location of the mesoscale convergence zone,thereby improving the precipitation location bias.关键词
地形重力波拖曳/四川盆地/强降水/数值模拟Key words
orographic gravity wave drag/Sihuan Basin/heavy rainfall/numerical simulation分类
天文与地球科学引用本文复制引用
靳双龙,艾真珍,季玉枝,张蓉蓉,衡志炜,徐昕..次网格地形重力波拖曳对四川东部一次强降水的影响和机理[J].南京大学学报（自然科学版）,2025,61(3):425-440,16.基金项目
国家电网公司总部科技项目(4000-202355453A-3-2-ZN) （4000-202355453A-3-2-ZN）
